炭酸カルシウムの結晶成長を制御するバイオミネラルタンパク質

抄録

  Biominerals, which are “hard tissues” mineralized by organisms, indicate distinctive microstructures formed by organic substances, which may regulate the crystal growth of minerals. Since biominerals have various excellent features including mechanical strength as a nano-composite material, many researchers have attempted to reveal their formation mechanism for industrial applications. In our studies, we have focused on the Japanese pearl oyster Pinctada fucata. P. fucata is used for pearl aquaculture in Japan and has fine shell microstructures consisting of calcium carbonates and some organic matrices. The shell is composed of three mineralized structures (two shell layers and the ligament) of different microstructures and an unmineralized outer organic membrane. Although all those mineralized structures contain calcium carbonate crystals, the crystal morphology, size, orientation and polymorphism are completely different among those structures. P. fucata may use a specific set of organic molecules to control the crystal growth in each structure. However, the information about the important organic molecules for the formation of calcium carbonates in the shell of P. fucata is still limited. In this article, we review several organic molecules associated with shell formation that we identified from those shell structures.